Official Discussion issued by the National Hurricane Center

Eight (AL082020) DATA RELEASED: 7/23/2020 4:00:00 PM UTC

Copy of official data

Tropical Depression Eight Discussion Number   4
NWS National Hurricane Center Miami FL       AL082020
400 PM CDT Thu Jul 23 2020

Satellite imagery indicates that the depression continues to become 
better organized, with the center near the eastern edge of a large 
and broadly curved convective area, with a second curved band to 
the east.  Several subjective and objective satellite intensity 
estimates have increased to 35 kt since the last advisory.  
However, surface observations, scatterometer data, and data from an 
earlier Air Force Reserve Hurricane Hunter mission show a large 
area of 25-30 kt winds south and east of the center, and no 35-kt 
winds to justify an upgrade at this time.  Thus, the initial 
intensity remains 30 kt.  A NOAA Hurricane Hunter aircraft is 
scheduled to investigate the depression this evening, and the 
current expectation is that they will find it is a tropical storm.

The center meandered a bit today, possibly due to reformation.  
However, the system now seems to have resumed a west-northwestward 
motion of 285/7 kt.  A mid-level ridge over the central United 
States is the predominant steering influence, and the global models 
forecast this ridge to build somewhat during the next several days. 
This should cause the depression to turn westward by 36-48 h 
and south of west after about 60 h.  The track guidance remains in 
good agreement with that scenario, although there has been a 
slight southward shift in the guidance envelope and the 
consensus models.  The new NHC forecast track is also shifted 
a little southward and has the center making landfall along the 
Texas coast in about 48 h.

The depression is in an environment of light shear with good 
anticyclonic outflow, and it will be over warm sea surface 
temperatures until landfall.  This should allow steady 
strengthening.  The new NHC intensity forecast has been increased 
to show a peak intensity of 50 kt just before landfall, followed by 
steady weakening and eventually dissipation after landfall.  The new 
intensity forecast is close to the intensity consensus.

The aircraft and scatterometer data show that the strongest winds 
in the cyclone are currently occurring about 70-90 n mi from the 
center.  This has caused the forecast wind radii to be expanded, 
and as a result a Tropical Storm Warning is needed for portions of 
the Texas coast.


Key Messages

1. The depression is expected to strengthen and it is likely to 
bring tropical-storm-force winds to portions of the Texas coast, 
where a tropical storm warning has been issued.

2. The tropical cyclone is expected to produce heavy rains across 
portions of Louisiana, southern Texas, and northern Mexico.  These 
rains could result in flash flooding and isolated minor-to-moderate 
river flooding.


FORECAST POSITIONS AND MAX WINDS

INIT  23/2100Z 26.1N  90.7W   30 KT  35 MPH
12H  24/0600Z 26.5N  91.9W   35 KT  40 MPH
24H  24/1800Z 27.1N  93.6W   45 KT  50 MPH
36H  25/0600Z 27.5N  95.3W   50 KT  60 MPH
48H  25/1800Z 27.6N  97.0W   50 KT  60 MPH
60H  26/0600Z 27.5N  98.5W   40 KT  45 MPH...INLAND
72H  26/1800Z 27.3N 100.0W   30 KT  35 MPH...INLAND
96H  27/1800Z 27.0N 102.0W   20 KT  25 MPH...POST-TROP/INLAND
120H  28/1800Z...DISSIPATED

$$
Forecaster Beven